Energy storage modules are known from the prior art, in respect of which reference is made for example to the German patent application DE 10 2005 041 604 A1, not previously published, in the name of the applicant and entitled “Device comprising at least one double-layer capacitor”. Energy storage modules of this type comprise a housing with components, for example capacitors, which are arranged therein and in which a combustible organic electrolyte is present. Under unfavorable boundary conditions, such an electrolyte can cause an explosion or a deflagration.
In capacitors, in particular double-layer capacitors, but also electrolytic capacitors, and lithium batteries, primarily organic electrolytes are used, which, if they escape in the event of a fault or damage, constitute a potential fire hazard or even explosion hazard. In some instances, said organic electrolytes also have a low vapor pressure. In order as far as possible to avoid an excessive increase in pressure and hence opening of the cell, electrolytes having a higher boiling point are also used. However, component parts comprising such electrolytes are then impractical for use at extremely low temperatures.
In present-day high-power systems which use readily combustible electrolytes, therefore, the passive safety is enhanced by extensive safety devices, for example redundant electronic monitoring devices, or installation sites are chosen where either critical ambient conditions can be precluded or any course of damage, e.g. a fire or an explosion, cannot cause harm to any persons.
This last means that the systems described often cannot be positioned at the functionally inherently favorable site.
In a typical case of damage, the modules release air admixed with gaseous electrolyte to the surroundings. A critical concentration of the gaseous electrolyte has to be precluded by rapid dissipation.
In the current technical development, the endeavor already resides in making the energy storage modules intrinsically safe, such that no case of fault can occur. Various proposals have already been made in respect of this in the patent application in the name of the applicant that was cited in the introduction.
DE 101 57 272 C2 discloses a lithium or lithium-ion battery in which a non-combustible sorbent is present in the associated housing. Furthermore, DE 101 28 672 A1 and DE 10 2005 007 607 A1 disclose capacitor arrangements which have in the housing in each case media which absorb capacitor emissions and which are situated at the bottom of the housing.